Biodiversity, taxonomy and metagenomics

GenBank (Benson et al. 2013) is a database that contains genetic sequences of species. Godfray (2007) proposed that metagenomics can replace taxonomy in identifying specimens. Indeed, giving names to specimens is not the primary role of taxonomy, the discipline being devoted to the description of new species and to reconstruction of phylogenies, focusing on both genotypes and phenotypes. So, the use of metagenomics for routinary species identification is a welcome technological aid to the study of biodiversity, freeing taxonomists from the burden of sorting and identifying biological material

Noise exposure potentiates exocytosis from cochlear inner hair cells

Noise-induced hearing loss has gained relevance as one of the most common forms of hearing impairment. The anatomical correlates of hearing loss, principally cell damage and/or death, are relatively well-understood histologically. However, much less is known about the physiological aspects of damaged, surviving cells. Here we addressed the functional consequences of noise exposure on the capacity of inner hair cells (IHCs) to release synaptic vesicles at synapses with spiral ganglion neurons (SGNs). Mice of either sex at postnatal day (P) 15-16 were exposed to 1-12 kHz noise at 120 dB sound pressure level (SPL), for 1 h. Exocytosis was measured by tracking changes in membrane capacitance (ΔCm) from IHCs of the apical cochlea. Upon IHC depolarization to different membrane potentials, Δ

Investigation on the Performance of a Compact Three-Fluid Combined Membrane Contactor for Dehumidification in Electric Vehicles

In this paper, the performance of a compact Three-Fluid Combined Membrane Contactor (3F-CMC) is investigated using Computational Fluid Dynamics (CFD), supported and validated with a good agreement by an experimental campaign made on a fully working prototype. This internally-cooled membrane contactor is the core component of a hybrid air conditioning system for electric vehicles (EVs) developed in a successful H2020 project called XERIC. In the adopted numerical approach, the conjugate heat and mass transfer inside the 3F-CMC is described by non-isothermal incompressible flows and vapor transport through a PTFE hydrophobic membrane. The sensitivity of the 3F-CMC performance to air/desiccant flow rates, temperature, humidity, and desiccant concentration is analyzed numerically through the validated CFD codes. According to this study, the moisture removal increases by the inlet humidity ratio, nearly linearly. Under the considered conditions (where the inlet air temperature is 26.2C), when the inlet relative humidity (RH) is 75% the moisture removal is about 450% higher than the case RH = 37%, while the absorption effectiveness declines about 45%. Furthermore, this study shows that the amount of absorbed vapor flux rises by increasing the airflow rate; on the other hand, the higher the airflow rate, the lower is the overall absorption efficiency of the 3F-CMC. This investigation gives important suggestions on how to properly operate a 3F-CMC in order to achieve the requested performance, especially in hot and humid climates

A possible common explanation for several cosmic microwave background (CMB) anomalies: A strong impact of nearby galaxies on observed large-scale CMB fluctuations

In Luparello et al. 2023, a new and hitherto unknown CMB foreground was detected. A systematic decrease in Cosmic Microwave Background (CMB) temperatures around nearby large spiral galaxies points to an unknown interaction with CMB photons in a sphere up to several projected Mpc around these galaxies. We investigate to which extent this foreground may impact the CMB fluctuations map and create the so-called CMB anomalies. Using the observed temperature decrements around the galaxies, and making some general assumptions about the unknown interaction, we propose a common radial temperature profile. By assigning this profile to nearby galaxies in the redshift range $z=[0.004,0.02]$ we create a foreground map model. We find a remarkable resemblance between this temperature model map based on nearby galaxies and the Planck CMB map. Out of 1000 simulated maps, none of them show such a strong correlation with the foreground map over both large and small angular scales. In particular, the quadrupole, octopole, as well as $\ell=4$ and $\ell=5$ modes correlate with the foreground map to high significance. Furthermore, one of the most prominent temperature decrements in the foreground map coincides with the position of the CMB cold spot. The largest scales of the CMB and thereby the cosmological parameters, may have important changes after proper corrections of this foreground component. However, a reliable corrected CMB map can only be derived when suitable physical mechanisms are proposed and tested.Comment: 5 pages, 4 figures, revised version which is accepted for publication in A&A Letter